Electric switch.



6. WRIGHT.

ELECTRIC SWITCH. APPLICATION FILED MY 5.1915.

Patentefl Dec. 31, 1918..

\nventor:

cmbe t Wri ht, y,

Hi5 'Attorn eg UNITED STATES PATENT @FFTQE.

GILBERT WRIGHT, OF SOHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRICCOMPANY, A CORPORATION OF NEW YORK.

ELECTRIC SWITCH.

T 0 (1 whom it may concern:

Be it known that I, GILBERT VVRIGHT, a citizen of the United States,residing at Schenectady, county of Schenectady, State of New York, haveinvented certain new and useful Improvements in Electric Switches, ofwhich the following is a specification.

My invention relates to electric switches and the like, and moreparticularly to the construction and inclosure of electric switches insuch a way as to minimize the danger of operating and working with themand with the apparatus that they control. My invention comprises variousfeatures and details of operation and construction and variouscombinations and arrangements of parts that can best be disclosed by thedescription of a particular apparatus embodying them, -its scope beingindicated in my claims.

In the accompanying drawings, Figure 1 is a side elevation of theapparatus with the switch closed, the side of the inclosing casing beingcut away.

Fig. 2 is a view from beneath, various parts being in section at asurface corresponding to the broken line 2-2 in Fig. 1.

Fig. 3 is a view similar to Fig. 1 with the switch open.

Fig. 4 is a side view of a locking device.

Referring first to Figs. 1 and 2, it Will be seen that the amiaratusshown comprises a switch proper 10 of ordinary three blade constructionmounted on a base 11 of slate or other insulating material. Also mountedon the base 11 and appropriately connected with the switch 10 are fuseholding means 1: shown as in the form of receptacles oi the Edison screwtype adapted to receive or dinary plug fuses. secured to the bottom ofnursing 13 which incloscs the switch 10 and the receptacles i2 and otheraccessory parts. This casing 13 is shown as a substantial sheet-iron boxwith its upper and lower ends rounded in front; preferably its joints orseams are electrically welded. The box proper has upper and loweropenings where thus rounded, and rounded covers it and 15 are providedto close these openings. The cover l-l (for as the covers 14 and 15 areexactly alike onlyone of them need be described) has a twocared bracket16 ot' channel-like form welded to its lower edge, and this bracket 16(its between brackets or cars 17, l? fastened to Specification ofLetters Patent.

The switch base 11 is Patented Dec. 31, 1918.

Serial No. 25,909.

the front portion 18 of the box proper between the aforesaid openingsand is pivoted to said brackets 17 by a pin or bolt 19. Through switchactuating means presently to be described the covers 14: and 15 are sointerlocked with the switch 10 that the latter must be actuated to openthe circuit before either cover can be opened. The covers 1% and 15always tend to close under the action of tension springs 20, 20. Theupper cove! 1% gives access to the switch 10; the lowe1 cover 15 to thefuse plug receptacles 12.

The switch apparatus shown being intended for push and pull operationand also to give a quick make and break, its actuating means includes areciprocating operating member 21 that extends through the casin front18 and a spring mechanism interposed between said member and the switchproper It). The member 21 comprises two parallel strips 23, of sheetmetal secured together and spaced apart in any suitable way, and isprovided with a convenient handle. The member 21 slides between thebrackets 17, 1'5 and between the cars of the brackets 16, 16 and in waysin a channel-like girder 524 that extends across the casing 13 behindthe front portion 18, These ways, itwill be seen, are formed by thesides of the channel 2% and by depending extension pieces 25 attached tobrackets or cars 26 secured to the lower side of the front portion 18 byscrews 27 that extend down through the brackets 17, 11?. Coming, now, tothe spring mechanism through which the switch 10 isordinarily actuated,it will be seen that on the inner side of each of the bracket extensions25 a. rocker member 2a is pivoted at 29. and to the ends of the rockers28, 25% (on their outer sides) the forward ends of links 50, 30 arepivoted by means of a pin 31. The rear cuds of th links 3!), 2-30 arepivoted at 32, 32 to logs or ears attached to the inner side of theinsulating bar 3-1 that unites the free ends of the switch blades. 0nthe pin 31 (but between the ends of the rockers 28, 28) is pivoted ablock 36 in which is secured one end of a rod 37 which slides freelythrough a block 38 pivtnied at 33) between the lower ends of the strips523, of which.

spring, 41 that serves mainly to cushion the movements of the parts andto take up backlash,

From the foregoing description it will be evident that when the partsare in the positions shown in Fig. 1 and pressure is applied to themember 21 to push it inward the pivot 89 will move downward and towardthe pivots 21), 29, and that the spring will be compressed and willexert on the block 36 a pressure tending to hold the switch 10 closed.As, however, the pivot 39 passes the line of centers oi the pivots 29,29and 3l,which is a. dead center for the parts 28, 28 and 37,-the spring40 will be left free to expand and throw open the switch 10 as shown inFig. 3; and at the same time it will throw the member 21 inward as alsoshown in that figure. This action will be very rapid and powerful, sothat any arc that may be drawn will. be quickly broken. 'hen the partsare in the positions shown in Fig. 3 and a pull is exerted on the member21 the switch 10 will be closed with a similar quick action, and member21 pressed to its outward limit.

In the lower end of the member :21 is fixed a pin -12 whose protrudingends slide in slots in the bracket extensions 25, and thus limit the inand out. movement of. the 111811} her. It will be seen that if thespring it) should fail to throw the switch 10 in eitherdirection,whether from sticking; ot the parts, breakage of the spring,or any other cause,the pin will come against one end of an enlarged footportion -18 of each of the rockers 28, 28 and either positively open orclose the switch or start it so as to cause the spring to throw it.

So far nothing has been said regarding the interlocking of the switch 10with the covers 14, 15 except that it is accomplished through the switchoperating means. It has, however, been pointed out that the strips 23,23 of the operatin member :21 slide just between the edges or the earson the brackets 16, 16. From this fact and the various figures of thedrawing, it will be evident that when the member :21 is pulled out andthe switch 10 closed as in Fig. 1 the edges of said strips 23, willeffectually block such movement of said ears as must take place when thecovers 14, 15 are swung open; whereas when the men'iber 21 is pushed into open the switch 10 as shown in Fig. 3 the notches =14 in the strips23, will be opposite said ears and allow the covers to swing q'iitefreely. A very slight outward movement of the member 21 from theposition of Fig. 3. wholly insullicient to throw the switch, will blockthe covers 1i, completely. Finally, it will be observed that when theparts are as shown in Fig. 3 and the cover 14 has been opened it ispossible to take hold of the member 3i with the hand and move the switch10 toward the closed position, but that before the pivot 39 has passedthe dead center or the switch blades have approached their contactssuliiciently to cause any danger of arcing the lower ends of the rockerportions 43 will encounter the pins l2 and movenn-rnt will be blocked.It follows, therefore, that the switch 10 cannot be closed except by theoperating member 21; neither can it. be brought to an intermediateposition where it will remain if released.

It will be observed that in the member 21 there is a slot -15 and thatthe brackets 16,16 have extensions l6, 16 that approach one another veryclosely and overhang this slot, when the switch 10 is open and thecovers 14, 15 are closed (see By inserting the locking element 50 inthis slot l5 and snapping a padlock 51 in one of the holes 52, SSthereinit will be rendered impossible to manipulate the members 2'1 to closethe switch 10 or to open either at the covers 14, 15. lily inserting theelement 50 in simi lar slots 17, f? in the braciret ears 1?, 1?, openingof the cover 14 will be prevented without interference with the cover 15or with the manipulation of the switch 10. The various holes 52, 53 inthe element 50 allow the switch apparatus to be controlled by severalpersons, as the electrician in charge of repairing the motor controlledby it and the machinist in charge of machinery driven by said motor,sothat each will be protected against any other by merely using his ownpadlock.

What I claim new and desire to secure by Letters Patent of the UnitedStates, is:

1. The combination of a casing having an opening and swinging closuremeans therefor, an electric switch in said casing, op erating means forsaid switch includinga member which interposes directly in the path ofswing of said closure means except when the switch is in open position,a yieldable connection between said operating means and said switchwhereby the latter is moved with a snap action, and means for lockingthe switch open whilethe closure means remain open.

2. The combination of a casing having an opening and swinging closuremeans therefor, a switch in said casing, reciprocating actuator for saidswitch including a mernher which inter-poses directly in the path ofswing of said closure means except when the switch is open, a rockerconnected to said switch and mounted on a stationary axis, and a springconnection between said rocker and said actuator adapted to be movedfrom side to side of said rocker axis by said actuator.

ii. The combinat on of a casing having an opening with a door therefor,a switch in said casing, a reciprocating actuator for said switch havinga member which directly intel-poses in the path of swing of said doorexceptwhen tl .2 switch is in open position, a rocker connected to saidswitch, a spring connecting said rocker to said actuator, andinterlocking means to prevent the'closure 01' said switch while saiddoor remains in open position.

4. The combination of a casing having openings at opposite ends of oneside and an intervening central portion, doors hinged to said centralportion, a switch in said casing, and a reciprocating actuator for saidswitch having a notched member passing through said central portionadjacent said hinges and adapted to interpose directly in the path ofswing of said doors except when said switch is open.

opening and movable closure means therefor; a switch in said casingandactuating means for said switch inclu inga pull and push operatingmember which extends out through the wall of the casing in the path ofmovement of said closure means in opening, said member being notched soas to permit opening of said closure means when the switch is open, aspring mechanism interposed between said operating member and the switchand adapted to give a quick make and break, and additional meansassociated with said member for opening and closing the switchpositively if said spring mechanism fails to do so.

In Witness whereof, I have hereunto set my hand this 30th day of April,1915.

GILBERT WRIGHT.

